Commutator slotting device



March 27, 1945. I

A. R. VOLZKA COMMUTATOR SLOTTING DEVICE Filed June 2, 1943 INVENTOR. v ,mzwa Jazz/ 1,

A ORNEY.

Patented Mar. 27, 1945 1 UNITED, STATES PATENT OFFICE coMMU'rAToR SLOT'IING' DEVICE Arthur R. Volzka, Racine, Wis. Application June 2-, 1943,. Serial No. 489,423

3' Claims.

My invention relates to slotting devices and more particulraly to a typeof device that is employed for undercutting the insulationbetween the segments of a commutator such asis used on generators, direct current and universal motors. In repairing commutators it is imperative-that the mica insulations between the segments be out below the periphery of the refaced commutator. It is also necessary that this cut'between the segments be kept in parallel alignment with the face of the commutator. Many devices on the market are constructed in a manner to produce a radial path. high in the center and low on the forward and rearward end. It is the purpose of my invention to provide a-device that will follow a diroot and level path at a lire-determined depth with provisions to arrest the travel of the tool, so

asto insure a uniform path of a pre-determined depth and length.

Other and further objects of my invention will become more apparent as the description proceeds when taken in conjunction with the drawing in-which I Figure 1 is a perspective view of the completely assembled device, showing the motor which acts as an actuating means and an armature in phanttom,

7 Figure 2 is a fragmentary plan view illustrating the manner in which. the cutting tool engages the slot between the commutator segments,

' Figure 3 is a fragmentary cross-sectional view of the driving and sliding mechanism,

Figure 4 is a cross-sectional view of the slidably mounted adjustable spindle which acts as a shaft mounting for the armature,

Figure 5 is a cross-sectional view of the other slidably mounted spindle for the armature shaft,

and I Figure 6 is a detail of the adjustment sleeve for controlling the length of the cut to be taken.

Similar characters of reference indicate corresponding parts throughout the several views and referring now to the same the character II) shows a support acting as a mounting for a motor l I, shown in phantom in Figure 1. This support I0 is pivotallymounted in bearings I2 and I2 which are fastened to a base plate I3. The

plate I3 slidably engages channels and I4 ara housing for a bearing I i in which is journaled an arbor" IE which is shaped toa contour, and made adaptable to receive a cutting wheel I9 on one end and a driven. pulley on the other end. 5 The pulley 20 is actuated by means of a belt 2I leading toa pulley 22 on the motor II. A base plate 23 on which the vertical standards I5 are attached,v is fastened to a bed plate 24 and a support arrangement consisting of a bolt 25 thread 10 edly engaging a yoke 26 in which is mounted a wheel 2'! is fastened to the support I0 near the depending end that supports the arbor I8. A resilient member 28 inserted over the bolt 25 permits the support IIlto rest on the yoke 26 and a 15 wing nut 29 acts as a clamping and adjusting means for the entire assembly. The wheel 21 mounted. in the yoke 26' provides a slidable bear-- ing for the depending end of the support II], the wheel 21 rotatably contacting the base plate 23 20 while the base plate I3 slides forward and backward in the channels I4.

The sliding motion is obtained by means of the manual. movement of a lever 3|] fastened to a link member 3I which link member is hingedly '25- supported at its lower end to the depending end of the base plate 23 at 32. The link member 3! has a rod. 33 fastened to its upper end at 34 and the rod- 33 engages an adjusting block- 35 which is fastened to the support It! at 36. The rod 33 is 3'0 held in any pro-determined position by means of in Figure 2 and the amount of travel of the support III is governed. by the contact of the lever 30 with the depending end of the support ID in which the arbor I8 is journaled. By referring to Figure l of the drawing it will 40 be noted that the bed 24 supports a longitudinal shaft 40 provided with a key way 4| cut into and extending the full length of the shaft 40. lhere are two supports 42 and 42 slidably engaging the shaft 40 and provided with a key 43 engaging the keyway ll of the shaft 40. These supports are provided with hollow spindles 44 and 44' which act as supporting means for the ends of armature shafts such as the armature 45 shown in phantom. The support 42 is further provided with an adjusting screw 46 held in place by a nut 41 to take care of the accurate adjustment necessary to permit the revolving of the armature when the cutting wheel I9 on the arbor I8 enters the groove 38 of the commutator. Obvious- 66 ly the supports 42 and 42' may be placed in a the shaft 40.

In operation the device functions as follows.

An armature and commutator assembly mounted on a shaft are placed'within the hollow spindles 44 and 44' of the supports 42 and 42. These supports are rigidly fastened to the shaft 40 after they have been slidably brought into position. The screws 31 in the adjustment block 35 are then loosened so that the rod 33 is free to move forward and backward in the adjustment block 35. The cutter I9 is placed in proper alignment with the insulation in the grooves 38 of the commutator 39 and the thumb nut 29 is adjusted on the bolt 25 so that the proper depth of the cut is obtained. It is then necessary to place the cutter l9 to the extreme end of the cummutator or the distance that the operator wishes to travel in his operation of slotting the insulation and the entire slide I is brought in direct relation with the lever 30 where it contacts the bearing IT. The screws 37 in the block 35 are then fastened and as the lever 33 is pulled forward away from the bearing H the entire sup port I!) will be moved forward in the channels l4 and i l to a position at the open end of the commutator. When the motor is put into operation being actuated by the electric current the arbor l8 supporting the cutter I9 will be revolved by means of the belt 2! and the manually operated lever 39 will carry the cutter l9 forward and backward in the slot 38 until the desired depth has been obtained when the armature is revolved so that the cutter l9 will be in proper alignment with the next slot on the commutator and this operation is continued until all slots in the commutator have been undercut.

It is manifest to anyone familiar with the art that the support It will keep the cutter IS in proper alignment and if desired the arbor I 8 supporting the cutter [9 may be integral with the shaft of the motor H in which case the motor will be mounted on'the depending end of the support it thereby eliminating the belt 2|, the

driven pulley and the bearing I7.

While I have herein shown a single embodiment of my invention for the purpose of clear disclosure it is manifest that any changes may be made in the arrangement, size and configuration of the various parts within the scope of the appended claims.

What I claim and desire to secure by Letters Patent in the United States is:

1. A device of the character described comprising in combinations, bed plate, said bed plate provided with a pair of channels, a base plate slidably mounted within said channels, a horizontal support pivotally mounted at one end to said base plate, means for vertical adjustment of the depending end of said horizontal support, said means slidably engaging said bed plate, adjustable spindles slidably attached to said bed plate in a manner to permit horizontal adjustment, said spindles adapted to receive the ends of a shaft supporting an armature and commutator, a, revolving arbor journaled within a motor attached .to said support at its depending end, said arbor provided with'a radial cutter placed in direct alignment with the center of the commutator on said armature, a manually operated lever terminating into a link member, which link member is pivotally attached to said bed plate on one end and an adjustable mounting on the other end, said adjustable mounting attached to said horizontal support in a manner to permit a variation in the length of the forward and backward stroke of the horizontal support in said channels acting as a sliding support for said base plate, thereby permitting the radial cutter to assume an arrested adjustable path along the face of said commutator when removing a portion of insulation between the segments thereof.

2. A device as described inclaim 1 in which the spindles are rotatably mounted and made adjustable by means of a screw thread operated by a thumb screw.

3. A device of the character described comprising in combination a bed plate, a base plate, a pair of horizontal channels acting as mounting means for said bed plate, a horizontal support pivotally mounted at one end to said base plate, an arbor journaled at the depending end of said horizontal support, an adjustable support for vertically adjusting the parallel relation between said bed plate and horizontal support, revolving means on said adjustable support to permit its free movement on the surface of said bed plate, a radial cutter mounted to one end of said arbor, a driven pulley mounted to the other end of said arbor, a motor, said motor mounted to said horizontal support and acting as an actuating means for revolving said arbor by means of said driven pulley, a pair of support members slidably engaging said bed plate, said support members arranged to journal an armature and commutator mounted on a shaft in direct alignment with said radial cutter, a manually operated lever, a link member, said lever mounted on said link member which has one end pivotally mounted to said bed plate, the other end pivotally mounted to a rod, said rod slidably engaging a contact member on said horizontal support, and means for retaining'said rod at a predetermined position within said contact member to vary the forward and backward movement of the horizontal support when actuated by said manually operated lever, thereby permitting the arrest and adjustment of the path taken by said radial cutter over the face of said commutator.

ARTHUR R. VOLZKA. 

